Answer with explanation:
The coordinates of four points are A(1, 1), B(4, 4), C(7, 1), and D(4, −2).
Plotting the four points in the two dimensional Coordinate plane
When you will plot these points you will get the shape of a Quadrilateral.

As all sides are equal, so this can be Square or Rhombus.
Slope between two points (1, 1), and (4, 4) is

⇒Prodct of slopes is -1, showing that lines which are sides of Quadrilateral are Perpendicular.
⇒As angle between sides measures 90°.So, the Quadrilateral is Square.
→Square